A procedure has been developed, based on centrifugal elutriation, for obtaining enriched populations of cells from embryonic rat cerebra. Methods designed to obtain purer cell fractions are being investigated. Dissociated murine dorsal root ganglia cells were grown in vitro and cultures containing up to 90-95% neurons were obtained. The cell surface components of specific types of CNS, PNS and transformed neural cells will be compared. Current studies of the sialoglycolipd composition of solid neuroblastoma tumors will be continued.